Stone-chisel.



1.70. PLAISTED. STONE GHISEL.

APPLICATION FILED JAN. 7,1911` Patented Sept. 26, 1911.

Inventor Witnesses r l Attor'neys UNITED STATES PATENT OFFICE.`

ALBERT C. PLAISTED, OF MANCHESTER, NEW HAMPSHIRE, ASSIGNOR OF ONE-HALF TO ORRIN L. HAZELTON, OF MANCHESTER, NEW HAMPSHIRE.

STONE-CHISEL.

Specification of Letters Patent.

Application led January 7, 1911.

Patented Sept. 26, 1911.

Serial No. 601,457.

`State of New Hampshire, have invented a `new and useful Stone-Chisel, of which the following is a specification.

This invention relates to stone working, and more especially to the tools employed therein; and the object of the same is to provide an improved chisel or dressing tool whereby the bit ends of the blades may be repeatedly ground and reground, and new blades can be used even after the blade which forms an extension of the stock has been very much worn away by repeated grinding.

To this end the invention consists in the means employed herein for connecting the side blades to the stock, and in the details of construction as set forth in the following specification and claims, and as shown in the drawings wherein- Figure 1 is a perspective view of my improved chisel ready for use. Fig. 2 is a central vertical longitudinal section thereof. Fig. 3 is a cross section on the line 3-3 of Fig. 2. Fig. 4 is a central vertical section showing one manner of securing two side blades to a stock which has been worn away. Fig. 5 is a perspective view of the lower end of a chisel having bits of other shape than those shown in Fig. `1, and Fig. 6 is a perspective view sho-wing my preferred manner of securing the side blades to a stock which `has been worn away.

In the drawings the numeral 5 designates the handle and 6 the stock of this improved chisel, the latter extended into a central blade 7 having its lower edge sharpened `into a bit 8 which may have any suitable configuration as shown at 8O in Fig. 5. The handle and stock are formed integral, and

. between them is an integral head 9, preferably having the form of a cube as shown,

and in opposite sides thereof are rectangular recesses 10 which may open upward through the head and outward through its side faces, but which must open downward through the head so as to form shoulders 11.

The numeral 17 designates the side blades whose bits are sharpened as at 18 and may have any suitable configuration as shown at 180 in Fig. 6, and at the upper end of each side blade is formed an integral rectangular tenon 20 adapted to fit the recess 10, and

each side of the tenon an upwardly-facing shoulder 21 adapted to rest against the shoulder 11 of the head 9, all as best seen in Fig. 1. In my preferred construction of the side blades, they also have upwardly facing shoulders 22 across their inner faces as seen in Fig. 6.

25 is a bolt passing through the two side blades and the interposed stock at a point beneath the tenons 20, and 26 is the nut on the bolt. As above intimated, the bit may be ground to any desired shape, but the grinding is preferably done on both sides of the blades.

The parts of this chisel are assembled when they are new as best seen in Fig. l, and the tool is used as usual. become dulled the parts are disconnected and the bits ground olf on both sides, care being taken that the cutting edges are caused to stand in alinement when the parts are reassembled for continued use. In this way it will be clear that in time the central blade 7 which is an integral part of the stock 6 will be ground off up to a point quite near the bolt 25, and I then preferably cut off its ends straight as shown at 27 in Fig. 4: or Fig. 6. Even after the central blade has thus been worn away and cut olf, the chisel can still be used as seen in Figs. 4L and 6 by applying two new and possibly quite lono side blades in the place of those whic have been worn o with the central blade, and have therefore become useless. It is true the use of two side blades without an intermediate blade between them will cause the side blades to converge as shown in these views, but the same bolt 25 passing through the same holes in the new blades and in the stock will hold the parts together as it did when they were al1 new. These substitute per end of the blade rest beneath the shoulders 22 on their inner faces, but when they do have such shoulders the latter will be so disposed as to rest beneath the lower ends 27 of the stock when the Shoulders 2l at the upper end of the blade rest beneath the shoulders 11 of the head 9. Those who are experienced in this art will appreciate the necessity of very firmly supporting the blades from the stock, both in order that they shall not get out of alinement with each other and thereby produce injury on the work, and in order that they will firmly resistI the blows upon the handle. Further than this I consider it unnecessary to detail the uses to which such a stone chisel may be put. The parts are obviously entirely of metal, tempered as may need be; and the sizes and exact shapes are immaterial.

lVhat is claimed as new is 1. A stone chisel comprising` a stock eX- tended into a central blade sharpened to a bit, said stock having a laterally enlarged head with upright side recesses forming downwardacing shoulders; blades at opposite sides of said stock and central blade and of the same length as the latter, the side blades having elongated tenons at their upper ends removably litt-ing' said recesses and also having shoulders at opposite sides of the tenon engaging those on the head; and a bolt through the side blades and the stock below said tenons.

2. A stone chisel comprising a stock eX- j the head; and a bolt through the side blades I and the stock below said tenons.

ln testimony that I claim the foregoing as my own, I have hereto aiiiXed my signature in the presence of two witnesses.

ALBERT C. PLAISTED.

Witnesses:

CHARLES H. NIXON, LILY L. BELANGER.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents,

Washington, D. G. v 

